How do you factor this problem

x^2 + 4x = 4

a) you don't factor problems. You solve them. You factor expressions.

b) this is an equation. I presume you want to solve for x?

x^2 + 4x = 4
x^2 + 4x + 4 = 4+4
(x+2)^2 = 8
x+2 = ±√8
x = -2 ±2√2